Art and Science 



already familiar, and mischievous, so far as they 

 are possible at all, in respect of all those things 

 that enter so profoundly and intimately into 

 our being that in them we must either live 

 or bear no life. To vivisect the more vital 

 processes of thought is to suspend, if not to 

 destroy them ; for thought can think about 

 everything more healthily and easily than 

 about itself. It is like its instrument the 

 brain, which knows nothing of any injuries 

 inflicted upon itself. As regards what is new 

 to us, a definition will sometimes dilute a diffi- 

 culty, and help us to swallow that which might 

 choke us undiluted ; but to define when we 

 have once well swallowed is to unsettle, rather 

 than settle, our digestion. Definitions, again, 

 are like steps cut in a steep slope of ice, or 

 shells thrown on to a greasy pavement ; they 

 give us foothold, and enable us to advance, 

 but when we are at our journey's end we 

 want them no longer. Again, they are useful 

 as mental fluxes, and as helping us to fuse 

 new ideas with our older ones. They present 

 us with some tags and ends of ideas that we 



have already mastered, on to which we can 



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